"I think the guys are really buying into trying to play hard here and there's a lot of pride in our dressing room and we just got to keep showing it," Bruins coach Claude Julien said.

Backes, who spent his first 10 seasons with St. Louis before signing with Boston as a free agent, fought with former teammate Joel Edmundson late in the second to the delight of the Scottrade Center crowd. Backes dropped the gloves in retaliation for a hit on Bruins teammate David Krejci by Jori Lehtera and received an instigator and a 10-minute misconduct in addition to his fighting penalty.

"I felt like they were trying to get the game back by trying to intimidate us and hitting us all over the place and I don't think it really matters how it happens," Backes said. "It's kind of, we've got to put an end to this, so I tried to put an end to it."

The Bruins fed off of the energy of Backes' return.

"You always want to step up for your teammate and `Backs' the way he plays for our team and the things he does every night, it's great to be able to go to battle for him and come up with a win for him," Marchand said.

The Bruins went up 4-0 when Krug scored his first goal in 30 games on a power play early in the second period. It was Boston's sixth goal with the man advantage in six games.

Bruins defensemen Adam McQuaid (upper body) and Colin Miller (lower body) left the game in the first and third period, respectively.

NOTES: Blues fans gave Backes a standing ovation following a video tribute during the first period. ... F Vladimir Tarasenko, the lone Blues player selected to the All-Star Game, played in his 300th game. . Rask and Marchand will represent the Bruins in the All-Star Game.